A UN-led inquiry into the murder of Jamal Khashoggi has determined that the dissident journalist was the victim of a “brutal and premeditated killing” which was “planned and perpetrated” by Saudi Arabian officials.

According to the UN inquiry statement, Saudi Arabia “seriously undermined” Turkey’s efforts to investigate Khashoggi’s murder, which took place at the Saudi consulate in Istanbul on October 2 last year.

UN investigator Agnès Callamard said her team had reviewed “chilling and gruesome audio material” of the murder, which had been obtained by Turkish intelligence officials.

Saudi Arabia initially denied having anything to do with Khashoggi’s death, but later suggested that he died during an accidental“fistfight” with officials inside the building. Riyadh later shifted its account of events again, admitting that the murder was premeditated but carried out as a “rogue operation.”

US President Donald Trump has been reluctant to harshly criticize Riyadh over the murder, admitting that the financial relationship between the two countries was more important. Trump has faced increasing pressure at home by members of both parties to take a more forceful stance with Crown Prince Mohammed bin Salman.

Callamard also said she asked for an official visit to Saudi Arabia and said she had “major concerns” about the fairness of the legal process for the 11 people facing trial for the journalist’s murder.

The investigator said anyone with further knowledge or intelligence about the murder should come forward and share it before the release of a report in June which will make recommendations on accountability.

She added that “woefully inadequate time and access was granted to Turkish investigators to conduct a professional and effective crime-scene examination and search required by international standards for investigation.”